<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  {% extends "parent.html" %}
  {% block left %}
    我是son1里左侧内容
  {% endblock %}
  {% block right %}
    我是son1里右侧内容
  {% endblock %}
  {% block somevalue %}
    {{super()}}
  {% endblock %}
</body>
</html>